I would have a lot of sympathy for the passenger in question if she hadn't tried to pull the race card which clearly had no relevance here. The man she was sat next to simply wanted to have the entire row for himself and his son. He may not have been entitled to it, but there's absolutely nothing in the story indicating a racist motivation.

People who do this hurt actual victims of discrimination. Being a member of (another) minority, I despise this behaviour.